The present invention relates generally to intravenous (IV) liquid medicament infusion equipment, and more particularly to drip chambers, valves and attachment mechanisms.
One of the most widely used methods of medical therapy is the intravenous (IV) infusion of liquid medicaments and/or nutrients into the bloodstream of a patient. A familiar apparatus that is used in many IV infusion applications is an IV container, such as an IV bag or bottle, which contains the liquid to be infused into the patient.
When the IV container is a bag, or bottle, a rigid, hollow, sharpened IV spike is pushed into the container to establish a pathway for fluid communication through which the liquid can flow out of the container. The spike, in turn, is connected to or formed integrally with an inlet port of a small, elongated, transparent hollow container familiarly referred to as a xe2x80x9cdrip chamberxe2x80x9d, with the fluid pathway of the spike in fluid communication with the inlet port of the drip chamber.
Additionally, an IV line is connected to the bottom or proximal end of the drip chamber. Preferably, a means for controlling the flow (a roller clamp, pump, or other suitable flow regulating device) is engaged with the IV line, and a medical technician can manipulate the flow controlling means and thereby regulate fluid flow through the IV line. To complete the path for fluid communication from the IV container to the patient, a sharp needle is connected to the IV line to puncture the patient.
Usually, the container is elevated above the patient to establish a positive pressure head to force the fluid that is within the container through the drip chamber into the patient. Because the drip chamber is transparent, a medical technician can view the medicament as it passes (normally by dripping) through the drip chamber to aid the medical technician in establishing a predetermined flow rate of medicament into the patient as the medical technician adjusts the flow controlling means on the IV line.
While effective as aiding in the establishment of a predetermined fluid flow to the patient, existing drip chambers, as noted above, require the use of sharpened spikes to puncture the IV container containing the liquid. This is undesirable, particularly in the era of AIDS, because spikes, like other sharps instruments, can inadvertently puncture the bag or medical technician who is manipulating the spike and thereby potentially contaminate the bag contents or infect the technician with AIDS or other disease. Thus, as recognized by the present invention, it is desirable to avoid the use of sharp instruments whenever possible, while preserving the quick connection such instruments provide.
Further, it is desirable to connect and disconnect the drip chamber or other components in the IV system without spillage of medicament. As recognized by the present invention, such reduction in spillage can be obtained through the use of reflex valves which are compatible with spikeless drip chambers and other needleless IV components.
Accordingly, it is an object of the present invention to provide a valve apparatus in an IV drip chamber or other IV component for engaging a complementary fitting, without the need to use a sharp connector. Another object of the present invention is to allow connection and disconnection of components without the spillage of medicament. Yet another object of the present invention to provide a drip chamber which is easy to use and cost-effective to manufacture.
A drip chamber includes an elongated transparent container defining an elongated hollow chamber. The container has both a proximal end and a distal end. A cap covers the distal end of the container, and it includes a drip-forming tube, a cannula and an attachment element. The drip forming tube is disposed within the container while the cannula extends distally away from the tube and establishes a pathway for fluid communication between a IV medicament container and the drip chamber. The attachment element surrounds the cannula and is configured so as to removably engage the chamber with a connector.
In one presently preferred embodiment, the proximal end of the drip chamber is engageable with an IV tube and connector to establish a pathway for fluid communication between the drip chamber and a patient.
The cannula in the presently preferred embodiment, is metal, but the present invention recognizes that it may be formed from other materials such as plastic.
In another embodiment, the proximal end of the container is a solvent bondable port element in fluid communication with the chamber. In yet another embodiment, the proximal end of the container is also configurable as a luer fitting. The present invention recognizes that either a male or female luer fitting may be used in this embodiment.
On the distal side of the container, to retain the chamber with an IV medicament connector, an attachment element is used. In one embodiment, the attachment element is configured as a threaded collar fitting. In another embodiment, the attachment element is configured as a so called xe2x80x9cAxe2x80x9d clamp. The xe2x80x9cAxe2x80x9d clamp has an open and a normal retention configuration, and is biased to the normal configuration. Preferably, the clamp includes two clamp elements, two fulcrum bars and two retaining lips. More clamp elements, fulcrum bars and lips are possible, but two of each is the most efficient. Specifically then, the clamp elements each have a distal pincer end and a proximal squeezeable end. The fulcrum bars are then attached on one side to the clamp element and on the opposite side to the cannula element or cannula holding element. The fulcrum bars are long enough such that the distal pincer ends are separated when the clamp is in the normal configuration. Ideally, the pincer ends open to facilitate easy assembly of the connector. The distal pincer ends may also configured with a lip to engage a complementary surface on the connector. The connector can be the port of any IV device, but the port of an IV bag, or other source of fluid, is preferable. To further facilitate engagement of the xe2x80x9cAxe2x80x9d clamp, the lips include an angular surface which, when urged against the connector port, move the pincer ends open sufficiently to allow mating of the lip and the complementary connector surface.
In another embodiment, a drip chamber includes an elongated container defining a hollow chamber. The chamber has both a proximal end and a distal end. A cap preferably covers the distal end of the container and it includes a drip forming tube, a valve body, at least one valve member disposed in the valve body and a valve actuating element. The drip forming tube is disposed within the container while the valve body defines a pathway for fluid communication through the cap. The valve member is disposed in the body and is biased to a first configuration where the path for fluid communication is not established. That is, in the first configuration, fluid may not pass through the body. Additionally, the valve member is movable to a second configuration where fluid communication through the body is permitted. Also disposed in the valve body is the valve actuating element. This element defines at least one engagement surface for contacting a mating element. Contact with the mating element causes the valve actuating element to move against the valve member. This pressure causes the valve member to move to the second configuration.
A variation of the above includes a valve member defining an outer periphery that is interrupted at least once within the periphery. The interruption within the periphery allows the fluid to pass directly through the member when in the second configuration rather than around the member (although the fluid could also pass through and around the member as envisioned above). In other words, when the valve member is in the second configuration, the interruption within the periphery defines an opening in the valve member allowing fluid through the valve member and thus, through the body.
The proximal end of the drip chamber may be configured in a variety of ways. In one embodiment the proximal end is configured as a male luer fitting. In another the proximal end is configured with a solvent bonded IV tube. And in yet another the proximal end is configured as a female luer fitting.
In another preferred embodiment, an IV component connector includes a valve body, a valve member and a valve element. In this embodiment, the valve body has a distal and a proximal end which define a path providing fluid communication through the body. The distal end has an attachment element to engage a complementarily shaped connector or surface. The proximal end has an outlet providing fluid communication with a connected component.
The valve member in this embodiment is disposed in the body and defines an outer periphery that is interrupted within the periphery at least once. The valve member is biased to a first configuration where the path for fluid communication is not established through the body. Also, the member is movable to a second configuration where fluid communication is permitted. The valve element is also disposed in the body and defines at least one engagement surface distally beyond the body. This surface contacts a mating element from another component that causes the valve element to move against the valve member thus moving the valve member to the second configuration.
In one presently preferred embodiment, the attachment element is configured as a male luer fitting to removably engage a female luer connector.
In another variation, the component connected to the proximal end may be any of various other IV components as disclosed in U.S. Pat. No. 5,645,538 to Richmond and incorporated herein by reference. Particular attention is directed to FIGS. 13, 15, 18, 19, 22-30; and the Specification, column 2, lines 14-18.
These and other aspects of the present invention can best be appreciated in reference to the accompanying drawings in which like numerals refer to like parts, and in which: